Electrostatic deflection system



Nov. 10, 1953 w. J. OESTREICHER 2,659,022

ELECTROSTATIC DEFLECTION SYSTEM Filed May 22, 1951 -13 t .1 4 m) l INVEN TOR. WARREN J 0677' Rim/15A Patented Nov. 10, 1953 ELECTROSTATIC DEFLEQTIQN SYSTEM Warren J. Oestre'ic'her, Brooklyn, .N. Y., vassig-nor :to Tele King Corporation, a corporation ofew' ApplicationMayZZ, 1951,-Serial No.n227,65

This invention relates to electronic circuitelements and more particularly to a piezoelectric type .element.

One of the objects of this invention is a cathode ray control circuit with a minimum of power and wiring requirements.

A more specific object of this invention is an electronic lens including a piezoelectric element producing the electrostatic field of the lens.

Another object of the invention is a cathode ray tube especially for television in which an electrostatic focussing field is formed by a piezoelectric type element surrounding the cathode ray especially in a position where the cathode ray emerges from the cathode of the tube.

Still another object of the invention is a piezoelectric defiection unit adapted to serve as a source of high voltage for producing a high volt age electrostatic field especially for focussing electrons, with one or more metal electrodes permitting adjustment of field length, field intensity or any other characteristic of the electrostatic field.

An additional object of this invention is to form this piezoelectric unit in the shape of a ring type disk which may be mounted around the neck of a cathode ray tube forming an electrostatic field in the interior of the tube which imparts to the electrons a predetermined angular directivity.

These and other objects of this invention will be more fully apparent from the drawing annexed herewith in which Fig. 1 represents a circular in cross section electrostatic deflecting element embodying certain features of the invention.

Fig. 2 represents a perspective view of such an element.

Fig. 3 shows a modified piezoelectric unit as may be employed as an electrostatic transducer, or condenser microphone.

In Fig. l, I represents a ring-shaped body of rectangular cross-section, consisting of highly insulating piezoelectric material such as titanium oxide which has been subject to a high potential electrostatic field while being molded or pressed into illustrated form.

This type of piezoelectric material is known per so under the name electret.

Electrodes applied in the form of foils, plates or coatings, to both planar faces of ring I, are provided as shown at 2, 3 respectively, preferably but not necessarily slightly projecting over the inner opening 4 of ring I as shown, for example at portions 5, 6 respectively.

These electrodes form therebetween an electrostatic field under the .control of the electric charges impressed upon the particles of ring- I during its formation or molding, resulting in lines of force extending substantially parallel to the central axis of ring I, or opening 4 of ring I as exemplified diagrammatically in dotted line at 6.

A metal collar or tube 1 in galvanic contact with one of the electrodes, say electrode 3 serves to adjust, by axial movement in the direction of arrows 9, I0, position, length, intensity of the electrostatic field or any other appropriate electric characteristic or combination of characteristics.

Any other means for adjusting the electrostatic field may be provided Without exceeding the scope of the invention.

The entire unit is shown perspectively in, Fig. 2 without the adjustable inner tube 1. It may be slipped over the neck of a cathode ray tube especially for television reception as schematically indicated in Fig. 1 at II, where until I operates as and replaces a properly biased Wehnelt cylinder, thereby serving as part of an electronic lens or electronic gun.

In this Way not only the additional Wehnelt electrode and its mounting inside a cathode ray tube are dispensed with but also the high voltage source required for its operation is eliminated.

In Fig. 3, the dielectric material producing the electrostatic field is applied in the form of a disc I2 with electrodes I3, I4 attached thereto or formed therein. One of these electrodes, say It, is shown to be conductively connected or attached to a vibratable diaphragm I5 arranged to reproduce sonic or supersonic waves under control of a source of modulation schematically indicated at I6, or, conversely, to produce electric waves in a modulating circuit I6 under control of sonic or supersonic waves causing diaphragm I5 to vibrate.

In such an arrangement, the high D. C. po1arizing potential usually required to be applied to one of the electrodes of a condenser microplane or loudspeaker is eliminated; the electrostatic field produced by element I2 will replace such potential.

The invention is not limited to be applied to the circuit elements shown and described, or in the forms shown and described; it may be used with equal efiect anywhere electrostatic fields are used to affect the movement of electrons, or generally any electric condition in vacuum or in 3 ordinary atmosphere; all this may be done without exceeding the scope of this invention.

I claim:

1. In combination a cathode ray tube having a screen portion and a neck portion reduced in diameter with regard to said screen portion, an electron gun arranged in said neck portion, a molding of insulating material of high dielectric constant surrounding said neck portion in a posi tion over a predetermined distance in front of said gun and means including particles of said molding subjected to a high potential unipolar electrostatic field during formation of said molding for producing an electrostatic focussing field across the opening in said molding in a direction parallel to the axis of the tube and under control of the electric charges retained in said particles.

2. Combination according to claim 1 comprising electrodes attached on said molding on both sides thereof to form an electrostatic field efiective inside the neck of the tube.

3. System according to claim 1, wherein said electrodes are slightly projecting over said molding into the opening formed therein, and a metal 4 sleeve coaxial with said opening and attached to one of said electrodes and spaced from the other; said metal sleeve fitting over the neck of the tube and along said predetermined distance.

WARREN J. OES'I'REICHER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,024,705 Rutherford Dec. 17, 1935 2,230,649 Mason Feb. 4, 1941 2,284,039 Bruno May 26, 1942 2,420,864 Chilowsky May 20, 1947 2,565,158 Williams Aug. 21, 1951 2,571,163 Rines Oct. 16, 1951 2,596,494 Lynch May 13, 1952 2,607,858 Mason Aug. 19, 1952 FOREIGN PATENTS Number Country Date 348,573 Great Britain May 12, 1931 438,672 Great Britain Nov. 21, 1935 610,297 Great Britain 1 Oct. 13, 1948 

